The continuous and growing request of energy worldwide, together with the depletion of the oil and gas resources, lead to an increasing interest to develop and apply EOR techniques in order to improve the production of already exploited reservoirs. In this scenario, current chemical EOR technologies are not yet widely applied, mainly for the high costs associated and high volumes required. "New" technologies and renovated chemical approaches must be implemented in order to make the chemical EOR processes extensively used. Among them, Nanotechnology seems to have an extraordinary potential to change production processes.

Taking into account encouraging results recently achieved at laboratory scale using Nanoemulsions and aspiring to the field, the aim of this study was dual: on one hand render nanoemulsions cost effective and attractive for field applications, on the other hand, have a deeper understanding and knowledge of nanoemulsions mechanism of action and effect of on porous media.

The two goals have been pursued with an intense formulative work based on a particular "low energy" proprietary method and using both bulk fluid characterizations and core floodings. Particular attention has been reserved to effluents observation and characterization in order to reveal criticalities associated to the application of this technology.

A possible key role of the coexistence, in nanoemulsions, of small droplets size, surfactants mixture and solvent has been highlighted. In fact, these factors can favourably impact, in a synergic way, some critical parameters associated to oil recovery such as oil/water interfacial tension, wettability and oil viscosity. Surfactant adsorption/retention as well as rock/nanoemulsion interactions have been also evaluated.

The future applicability of nanoemulsion strongly depends on its costs that can be reduced decreasing the amount of surfactants and solvent present in the formulation. This surely has an impact on nanoemulsion intrinsic structure (i.e. average droplet size, surface area) but not necessarily on the efficiency of mobilization of residual oil in porous media. Furthermore, alternative injection approaches can induce additional savings.

The next phase foresees studies on injection strategies, the design of an up-scaled nanoemulsion production and nanoemulsion tuning on the basis of specific field parameters in order to render the technology suitable for a SWCTT.

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